# 折射率

${\displaystyle n={\frac {c}{v}}}$

## 水波的相對折射率

${\displaystyle n_{\text{AB}}={\frac {v_{\text{A}}}{v_{\text{B}}}}={\frac {\sin \theta _{\text{A}}}{\sin \theta _{\text{B}}}}={\frac {n_{\text{B}}}{n_{\text{A}}}}}$

## 介質的折射率

589.29 1.501 [1]

589.29 1.3330 [1]

1.31

1.661

Cytop 1.34 [9]
Sylgard 184 1.43

PETg 1.57

590 3.96 [11]
4.00

## 折射率是波長的函数

### 柯西公式

${\displaystyle n=A+{\frac {B}{\lambda ^{2}}}+{\frac {C}{\lambda ^{4}}}}$ [12]

### 康拉迪公式

${\displaystyle n=A+{\frac {B}{\lambda }}+{\frac {C}{\lambda ^{3.5}}}}$ [13]

### Herzberger公式

${\displaystyle n=A+B*\lambda ^{2}+{\frac {C}{\lambda ^{2}-\delta ^{2}}}+{\frac {C}{(\lambda ^{2}-\delta ^{2})^{2}}}}$ [14]

### 肖特玻璃廠公式

${\displaystyle n=A+{\frac {B}{\lambda }}+{\frac {C}{\lambda ^{2}}}+{\frac {D}{\lambda ^{4}}}+{\frac {E}{\lambda ^{6}}}+{\frac {F}{\lambda ^{8}}}}$ [14]

### Sellmeier公式

${\displaystyle N^{2}-1={\frac {A\cdot \lambda ^{2}}{\lambda ^{2}-D}}+{\frac {B\cdot \lambda ^{2}}{\lambda ^{2}-E}}+{\frac {C\cdot \lambda ^{2}}{\lambda ^{2}-F}}}$ [15]

## 複數折射率

${\displaystyle {\tilde {n}}=n+i\kappa }$  複折射率的實部即為尋常的折射率，而虚部則稱為消光係數（extinction coefficient），表示電磁波進入材料後的衰減量。

## 參考資料

1. Hecht, Eugene. Optics, Fourth Edition. Pearson Higher Education. 18 March 2003. ISBN 9780321188786.
2. ^ Morgan, Joseph. Introduction to Geometrical and Physical Optics. McGraw-Hill Book Company, INC. 1953.
3. ^ Charles D. Hodgman; Selby, Weast. Handbook of Chemistry and Physics, Thirty-Ninth Edition. Chemical Rubber Publishing Co. 1957.
4. ^ Frank L. Pedrotti; Pedrotti, Pedrotti. Introduction to Optics, Third Edition. Pearson Prentice Hall. 2006: 221. ISBN 978-0131499331.
5. ^ Silicon and Oil Refractive Index Standards 互联网档案馆存檔，存档日期2010-08-29.
6. ^ Meyrowitz, R, A compilation and classification of immersion media of high index of refraction, American Mineralogist 40: 398 (1955) (PDF). [2011-01-28]. （原始内容 (PDF)存档于2011-06-16）.
7. ^ RefractiveIndex.INFO - Refractive index and related constants. [2011-01-28]. （原始内容存档于2021-03-03）.
8. ^ Yang, Min K.; French, Roger H.; Tokarsky, Edward W. Optical properties of Teflon® AF amorphous fluoropolymers. Journal of Micro/Nanolithography, MEMS, and MOEMS. 2008-07, 7 (3): 033010. ISSN 1932-5150. doi:10.1117/1.2965541.
9. ^ Cytop. [2010-10-14]. （原始内容存档于2010-08-24）.
10. ^ 利物浦大學. Absolute Refractive Index. [2007-10-18]. （原始内容存档于2007-10-12）.
11. ^ Optical Properties of Silicon. [2009-05-31]. （原始内容存档于2009-06-05）.
12. ^ Rudolf Kingslake, Lens Design Fundamentals,p12, Academic Press 1978
13. ^ A.E.Conrady Applied Optics and Optical Design, part II,p659, Dover
14. Rudolf Kingslake, Lens Design Fundamentals,p14, Academic Press 1978
15. ^ Milton Laikin Lens Design p9 2006 CRC Press 978-0849382789